/Engine/Source/Runtime/Engine/Public/MaterialShared.h
Collect all possible PSO's which can be used with this material for given parameters - PSOs will be async precached
FGraphEventArray CollectPSOs ( [ERHIFeatureLevel::Type](API\Runtime\RHI\ERHIFeatureLevel__Type) InFeatureLevel, const FPSOPrecacheVertexFactoryDataList & VertexFactoryDataList, const [FPSOPrecacheParams](API\Runtime\Engine\FPSOPrecacheParams) & PreCacheParams, EPSOPrecachePriority Priority, [TArray](API\Runtime\Core\Containers\TArray)< FMaterialPSOPrecacheRequestID > & OutMaterialPSORequestIDs )